1. Technical Field
The present invention relates to a busbar and a method of manufacturing a busbar. Specifically, the present invention relates to a busbar which is connected to a power supply and supplies electricity to electric parts and relates to a method of manufacturing the same.
2. Related Art
A power supply circuit or the like conventionally uses a busbar which is connected to a power supply, such as a battery, and supplies electricity to electric parts and the like. The busbar is provided with an insulating coating therearound to prevent a short circuit between the busbar and another busbar adjacent thereto or the like.
For manufacturing such a busbar including an insulating coating, there are some methods. In a simple method, a heat-shrinkable tube is inserted into an electrically conductive member composed of an electrically conductive material and is heat-shrunk to form an insulating coating around the electrically conductive member. Such an insulating coating has a low heat resistance and is difficult to use in high-voltage or high-temperature sections. Applications of the insulating coating to automobiles are therefore limited. Another method of manufacturing a busbar uses insert molding to form an insulating coating. However, insert molding requires preparation of a dedicated mold, increasing costs of small lot products.
Accordingly, other methods are being examined, in which insulating resin is applied on the electrically conductive member and then cured to form an insulating coating. To be specific, in one of the methods which are being examined, thermosetting resin or ultraviolet curable resin is used as the insulating resin. The thermosetting resin or ultraviolet curable resin is applied to the electrically conductive member and is cured. However, it takes comparatively long time to cure the thermosetting resin. Accordingly, ultraviolet curable resin, which has been practically used in optical fiber cables, is attracting attentions. Moreover, curing of ultraviolet curable resin can be finished within a short period of time.
Patent Literature 1 discloses a method of applying ultraviolet curable material. The method uses two types of ultraviolet curable material having different viscosities so that coating film is formed so that bubbles are not involved between strands.
Patent Literature 1: Japanese Unexamined Patent Application Publication No. 4-272618